The former San Diego vocal dynamo will guest on the TV series that made him a national star on Tuesday and Wednesday, Feb. 18 and 19. His second-place finish in 2009 earned him a major label record contract, a devoted following and a spot as the lead singer in the legendary English rock band Queen, which may embark on a U.S. concert tour with Lambert later this year. (We'll have more on that in a moment.)

Lambert and 2006 "Idol" alum Chris Daughtry will be featured together on Tuesday and Wednesday's editions of the show. Both will serve as mentors on "Boot Camp," a new competition phase of the show that will be overseen by former "Idol" mainstay Randy Jackson. The camp is a two-day workshop designed to familiarize viewers with this year's 30 "Idol" semi-finalists before the show's live episodes begin airing and the viewer voting period kicks off.

It remains to be seen if this season will also see the return of other "Idol" alums, such as Chula Vista native Jessica Sanchez, who came in second on the show in 2012 and released her debut solo album last year.

However, the show's two new executive producers, Evan Prager and Jesse Ignjatovic, appear amenable to such a possibility. "We're always open to that," they told The Hollywood Reporter last month. "We collectively love the idea of bringing previous 'Idols' back to the show."

Now, back to the possibility of Lambert touring with Queen.

In an interview last week on England's BBC Radio 2, Queen guitarist Brian May suggested that U.S. shows with Lambert could happen as soon as this summer.

After collaborating with two of Queen's three surviving members for one song on "Idol" in 2009, Lambert first performed in concert in 2011 with Queen, whose original lead singer, Freddie Mercury, died in 1991. Lambert also performed a a few shows with Queen in 2012 and another with the band last fall in Las Vegas. He seems to fit in well with May and Queen drummer Roger Taylor.

"We've been talking to Adam Lambert," May told BBC Radio 2. "You know, we've already done some gigs with Adam, who is amazing. We (Queen) are ongoing, we can't help it. I think we all protested too much in the sense when Freddie went and we didn't want to talk about it and didn't want to be Queen for a while.

"But after a while you realize that people wanna hear the songs and see us do things. So, no matter what you call it, Roger and I do do stuff, and I think we'll be doing some more stuff this summer in fact, probably in the States."